First of all, measles breaks out every year in Beijing, and the number is very large (you can know how dangerous measles is). Taking 14 autumn and winter as an example, there were only two confirmed cases of measles in a company, which led the CDC to ask the health department within its jurisdiction to vaccinate 3,000 people in the company, which not only increased the burden on health care doctors, but also caused hidden dangers to the health of surrounding residents.

Most measles cases in Beijing are basically caused by floating population (this is not nonsense, not only the spread of measles, but also the spread of wild polio strains, but the main source is Xinjiang), because many floating population have not been vaccinated according to the immunization plan since childhood (you can see how low the emphasis on immunization planning is in many places by checking the vaccination rates in other places 1). Therefore, these people do not have enough immunity, which may be both the source of infection and the susceptible population. Therefore, it is a kind of welfare and care to vaccinate the vulnerable students in the foreign population for free. In many places in the suburbs of Beijing, vaccination is not popular, but they can't enjoy it;

Then talk about vaccines. I want to popularize a knowledge to the questioner, that is, antibody level. You know, after vaccination, you will never get sick, and the antibody level will decrease with age until it can't protect you. Many people can't produce antibodies after a chestnut hepatitis B vaccine, so don't think that it is unnecessary to fight again, especially in high-risk groups;

Finally, give some suggestions to the questioner: Get flu vaccine in winter, and let yourself or your family get pneumonia vaccine at 23 when you have time. These two are the most important things for adults at present. For the health of yourself, your family and even people around you, please don't neglect your health.